It is known that a considerable amount of motion picture content was created in a format suitable for television screens or theatrical projection with limited brightness. Such motion picture content (and other similar forms of image content) is referred to herein as legacy image content. Full light was typically used in creation of legacy image content whereby brilliant areas of light needed to be clipped, in order not to darken the entire scene. Deeper in the creative process, studio lighting, as well as professional still image studio lighting, needed to fill shadows to limit the range of scenes to typically a ratio of 1:3. However, as the brightness of digital displays has increased, artists have had wider discretion to use this wider range. This can be seen it different artistic lighting of modern movies, and a slow change in the aesthetic of motion picture art.
It is also known that, in recent years, there has been a migration way from fill lighting. As a result, motion picture content that intentionally have brilliant details that require the display to hit very high brightness levels, and intentional deep shadow detail that require the display to reproduce full blacks. This type of motion picture content (i.e., image content) is said to have Ultra High Definition (UHD) or High Dynamic Range (UHD).
Image content that reflects the imagery intentions of the director or other professional responsible for creating the image content (i.e., “the Director's Intent”) is referred to herein as “classic image content”. An example of classic image content is a movie (e.g., i.e., motion picture) that has been available in the world for viewing by the general public (e.g., in the form print film, DVD, etc) and that was created prior to the UHD capability in televisions. A common type of classic image content is legacy image content (i.e., legacy-type classic image content), which was created prior to the advent of playback equipment having UHD capability and, thus, often has low resolution and limited detail in the highlights and shadows.
Legacy-type classic image content is created by an image mastering professional (e.g., a “colorist”) through manipulation of image content that has not yet been subjected to the Director's Intent (i.e., original image content). For example, the original image content may be manipulated so that the color and illumination aesthetics are assumed to be just right and may include other artistic manipulations such as spatial effects (e.g., vignetting) and global effects (e.g., cross development). In this respect, it is common for the legacy-type classic image content to have been approved by the creator or director of the original image content and represents the content that is intended and preferred for public viewing.
The original image content is preferably as close to the as-captured original scene as currently exists or available. For example, the original image content can be in the form of an original camera film negative, raw digital data, or whatever is available closest to the original scene. Notably, the original image content does not bear the Director's Intent. However, relative to corresponding legacy-type classic image content, the original image content does bears more information in the form of resolution, detail in the highlight and shadows, and ability to recover and image with less damage. It is disclosed herein that the original image content can be from more than one or more sources.
Classic image content (legacy-type or otherwise) reflects the aesthetics that has been approved by the director (i.e., represents the Director's Intent) and that bears the color and stylistic look that would make for a preferred form of image content that is UHD compliant. This form of image content is referred to herein as UHD-compliant classic image content. A problem arising from prior art approaches for generating UHD-compliant classic image content is that the Director's Intent in classic image content does not anticipate UHD imagery. Accordingly, a perfect technical UHD processing of the original image content may be completely counter to the Director's Intent. As an example, in the classic image content an open window may have been intended to simply be white and ignored, but in UHD-compliant classic image content created using a prior art approach, the window may become so bright with so much distracting detail that other action in the room is overpowered. As another example, in classic image content, an up-view of a man looking down may have intended the sky in back of the man to be soft, but in the UHD-compliant classic image created using a prior art approach, the sky may be blindingly bright such that it overpowers facial expressions and creates a focus on the details in the sky (e.g., birds and clouds) rather than the facial expressions of the man. Thus, as shown in these examples, countermanding the Director's Intent, no matter how “accurate” technically, the artistic intent, and probably the storyline, is put in jeopardy.
Creating UHD-compliant classic image content via known approaches involves manipulating corresponding original image content to create corresponding UHD-compatible image content. More specifically, the visual characteristic of a frame or scene being created as part of the UHD-compliant classic image was manually matched to that of a corresponding frame or scene of corresponding classic image content by adjusting a series of parameters. In this “parametric” approach, the tools available to the professional conducting the UHD processing (e.g., a colorist) typically consist of a series of knobs (i.e., parametric knobs). These parametric knobs (e.g., each controlling on of red, green, blue, or grey brightness) are applied to the original image content in an attempt to match the color aesthetics in the classic image content. Although the professional conducting the UHD processing is assumed to have a basic and accurate translation from a film negative to positive in place as a simulation of print film, such professional would have also had a choice of types of film and modifiers. Because of the archaic chemical and electronic intermediates introduce many anomalies and variables into the UHD processing, compensating for anomalies and variables would require additional parametric knobs such as for adjusting contrast, brightness, toe and shoulder roll off, and the like. In the parametric approach, a human or a computer would adjust the knobs to get a reasonable match of the manipulated version of the original image content and the classic image content.
As understood by a person of ordinary skill in the art, one obvious limitation of this parametric approach to creating UHD-compliant classic image content is either having too few knobs or too many knobs, such that they become over-specified which can lead to contouring. For example, if an image has a continuous scale, the image shows distinct steps when such contouring occurs (e.g., using too few bits to represent an image is an easy way to introduce contouring). However, even with sufficient bits, if the representation of color intensity is not continuous or not continuously increasing with increasing intensity, contouring and other artifacts can occur an effect similar to banding. Another obvious limitation of this parametric approach to creating UHD-compliant classic image content is that any spatial effects (i.e., varying with space) such as, for example, intentional or accidental vignetting anywhere in the original process can lead to very bad results. For example, if the center of an image was initially darker than the edges and the printing process darkened the edges through vignetting, the parametric approach would choose a low contrast to balance brightness globally, although regionally the image aesthetic would be softened by lowered contrast and would produce a very different aesthetic than that of the Director's Intent.
Therefore, creating UHD-compliant classic image content in a manner that combines desirable imagery features of classic image content with desirable imagery features of corresponding original image content and that overcomes imagery limitations associated with known approaches for processing such original image content would be advantageous, desirable and useful.